选择具有强吸湿能力且难挥发的LiCl浓溶液作液膜相,以商品化的尼龙膜做多孔支撑体,以溶液沉积法合成聚偏氟乙烯为皮层,制备了复合支撑液膜.测试了复合支撑液膜的成膜规律和膜透湿性能.结果表明:运用溶液沉积法合成的复合支撑液膜与运用粘结法所合成的复合支撑液膜相比较,皮层与支撑层结合很好,皮层的厚度大大减少;具有很好的H2O蒸气渗透性能,几乎不能透过CO2;在保持铸膜液中致孔剂聚乙二醇2000的质量分数为2.4%不变的情况下,膜表面孔径、膜的H2O蒸气渗透的总传质系数、渗透速率和湿交换效率随着铸膜液中固含量的减少呈上升趋势.
A novel composite supported liquid membrane, which employs LiCl liquid solution immobilized in a porous support membrane to facilitate the transport of moisture, is prepared. To protect the SLM(Supported Liquid Membrane), two hydrophobic PVDF (Polyvinylidene Fluoride) layers are formed on both surfaces of the SLM. The membrane formation and characteristics are investigated. The results show that, the supported liquid layer and the two protective layers are in good contact and the layers are much thinner, from SEM observations; the vapor permeation performance is very good, while the CO2 permeation rate is almost near to zero; the total vapor transfer coefficient , the vapor permeation velocity, the moisture transfer efficiency and the aperture on the surfaces of the membranes increase with the mass fraction of the solid decreasing, when the mass fraction of the additive(PEG2000) was kept to be 2.4%.